A variety of approaches are known for dissipating heat generated by power semiconductor surface-mount (SM) devices. One approach is to use a ceramic substrate, such as alumina (Al.sub.2 O.sub.3), beryllia (BeO), or another ceramic material that may be modified to promote its heat conduction capability. Heat-generating integrated circuit (IC) chips, such as insulated gate bipolar transistor (IGBT) chips, are often mounted to ceramic substrates that conduct and dissipate heat in the vertical direction away from the chip. A heatsink may be attached to the opposite side of the substrate in order to dissipate heat to the surrounding environment. A heatsink may also be placed between the chip and substrate in order to increase heat transfer from the chip to the substrate. Because lateral heat transfer through a ceramic substrate is low compared to metals and metal-containing materials, power IC components have been mounted to thick-film conductors that increase heat transfer from the component downwardly to the underlying ceramic substrate.
From the above, it can be seen that various components may be employed to thermally manage power IC's on a ceramic substrate. Each of these components must be reliably soldered to adjacent components in order to survive numerous thermal cycles during the service life of the circuit assembly. In the past, sequential soldering operations have been required to better control the placement of each component following soldering, such that each component remains properly oriented and aligned with respect to its adjacent components. With each successive soldering operation, a lower temperature solder alloy is often used so as not to disturb the preceding solder joint. Accordingly, multiple assembly and joining operations are conventionally required to mount a power IC to a ceramic substrate. However, from the standpoint of process efficiency and costs, it would be desirable if the number of process steps could be reduced while maintaining an acceptable level of thermal management and design flexibility.